A risk of an electrical short between electrode pads of a semiconductor device can be reduced to thereby improve quality of the semiconductor device. During ball bonding in wire bonding, in each of the electrode pads of a semiconductor chip which are arrayed along an ultrasonic wave application direction (ultrasonic vibration direction), a ball at the tip of a copper wire and the electrode pad are coupled to each other while being rubbed against each other in a direction intersecting the ultrasonic wave application direction. Thus, the amount of AL splash formed on the electrode pad can be minimized to make the AL splash smaller. As a result, the quality of the semiconductor device assembled by the above-mentioned ball bonding can be improved.
Legal claims defining the scope of protection, as filed with the USPTO.
1. A manufacturing method of a semiconductor device which method forms a ball at a tip of a conductive wire passed through a capillary as a bonding tool, and performs wire bonding of the ball to an electrode pad of a semiconductor chip, comprising the steps of: (a) providing the semiconductor chip having a plurality of electrode pads formed in a main surface thereof, each of said electrode pads having aluminum as a principal component; and (b) applying an ultrasonic wave along an application direction to electrically couple the ball at the tip of the conductive wire to each of the electrode pads, the conductive wire having copper as a principal component, wherein in the step (b), when performing the wire bonding to, among the electrode pads, first electrode pads that are arrayed in a first direction along the application direction of the ultrasonic wave, the ball and each of the first electrode pads are coupled to each other while being rubbed against each other along a second direction transverse to the application direction of the ultrasonic wave.
2. The manufacturing method of a semiconductor device according to claim 1 , comprising, in step (b): moving a bonding head supporting the capillary along the second direction while the ball and each of the first electrode pads are being electrically coupled to each other.
3. The manufacturing method of a semiconductor device according to claim 2 , wherein the first electrode pads are arrayed around a periphery of the main surface of the semiconductor chip.
4. The manufacturing method of a semiconductor device according to claim 1 , wherein among the electrode pads in the main surface of the semiconductor chip, at least the first electrode pads that are arrayed in the first direction along the application direction of the ultrasonic wave have a rectangular shape with a long dimension extending along the second direction.
5. The manufacturing method of a semiconductor device according to claim 1 , wherein the conductive wire has a surface coated with a palladium plating.
6. The manufacturing method of a semiconductor device according to claim 1 , comprising, in step (b): reciprocating a bonding head supporting the capillary along the second direction while the ball and each of the first electrode pads are being electrically coupled to each other.
7. The manufacturing method of a semiconductor device according to claim 1 , wherein the electrode pads comprise second electrode pads arranged along the second direction, the method further comprising: applying the ultrasonic wave to the second electrode pads along the application direction to electrically couple the ball and each of the second electrode pads.
8. The manufacturing method of a semiconductor device according to claim 7 , comprising; applying the ultrasonic wave to the second electrode pads without rubbing the ball and each of the second electrode pads against each other along the second direction.
9. A manufacturing method of a semiconductor device which method forms a ball at a tip of a conductive wire passed through a capillary as a bonding tool, and performs wire bonding of the ball to an electrode pad of a semiconductor chip, comprising the steps of: (a) providing a multiple lead frame having a plurality of device areas provided in a matrix arrangement, the device areas each having a chip mounting part suitable for receiving a semiconductor chip, and a plurality of leads arranged around the chip mounting part; (b) mounting a semiconductor chip having a plurality of electrode pads formed in a main surface thereof in one of the chip mounting parts, each of said electrode pads having aluminum as a principal component; (c) applying an ultrasonic wave along an application direction to electrically couple the ball at the tip of the conductive wire to each of the electrode pads of the semiconductor chip, the conductive wire having copper as a principal component and being guided by the capillary; (d) sealing the conductive wire and the semiconductor chip with a sealing resin; and (e) cutting/severing the leads projecting from a seal formed by the sealing resin, from the lead frame, wherein in the step (c), when performing the wire bonding to, among the electrode pads, first electrode pads that are arrayed in a first direction along an application direction of the ultrasonic wave, the ball and each of the electrode pads are coupled to each other while being rubbed against each other along a second direction transverse to the application direction of the ultrasonic wave.
10. The manufacturing method of a semiconductor device according to claim 9 , comprising, in step (c): moving a bonding head supporting the capillary along the second direction while the ball and each of the first electrode pads are being electrically coupled to each other.
11. The manufacturing method of a semiconductor device according to claim 10 , wherein the first electrode pads are arrayed around a periphery of the main surface of the semiconductor chip.
12. The manufacturing method of a semiconductor device according to claim 9 , wherein among the electrode pads in the main surface of the semiconductor chip, at least the first electrode pads that are arrayed in the first direction along the application direction of the ultrasonic wave have a rectangular shape with a long dimension extending along the second direction.
13. The manufacturing method of a semiconductor device according to claim 9 , wherein the conductive wire has a surface coated with a palladium plating.
14. The manufacturing method of a semiconductor device according to claim 9 , comprising, in step (c): reciprocating a bonding head supporting the capillary along the second direction while the ball and each of the first electrode pads are being electrically coupled to each other.
15. The manufacturing method of a semiconductor device according to claim 9 , wherein the electrode pads comprise second electrode pads arranged along the second direction, the method further comprising: applying the ultrasonic wave to the second electrode pads along the application direction to electrically couple the ball and each of the second electrode pads.
16. The manufacturing method of a semiconductor device according to claim 15 , comprising; applying the ultrasonic wave to the second electrode pads without rubbing the ball and each of the second electrode pads against each other along the second direction.
17. An ultrasonic wire bonding method for electrically coupling a ball at a tip of a conductive wire to each of a plurality of electrode pads associated with a semiconductor chip by means of a bonding tool having a capillary through which the conductive wire is passed, the conductive wire having copper as a principal component, the electrode pads having aluminum as a principal component, the method comprising: (a) providing a semiconductor chip having a plurality of electrode pads formed in a main surface thereof, the electrode pads including first electrode pads arrayed in a first direction of the semiconductor device and second electrode pads arrayed in a second direction of the semiconductor device, the second direction being transverse to the first direction; (b) applying an ultrasonic wave along an application direction to electrically couple the ball at the tip of the conductive wire to each of the first electrode pads, the application direction being the same direction as the first direction along which the first electrode pads are arrayed; and (c) applying an ultrasonic wave along said application direction to electrically couple the ball at the tip of the conductive wire to each of the second electrode pads; and in step (b), applying the ultrasonic wave along said application direction, while rubbing the ball and each of the first electrode pads against each other along the second direction.
18. The ultrasonic wire bonding method according to claim 17 , comprising, in step (b), moving a bonding head supporting the capillary along the second direction while the ball and each of the first electrode pads are being electrically coupled to each other.
19. The ultrasonic wire bonding method according to claim 17 , comprising, in step (b), reciprocating a bonding head supporting the capillary along the second direction while the ball and each of the first electrode pads are being electrically coupled to each other.
20. The ultrasonic wire bonding method according to claim 17 , comprising, in step (c), applying the ultrasonic wave along said application direction, without rubbing the ball and each of the second electrode pads against each other along the second direction.
21. The ultrasonic wire bonding method according to claim 17 , wherein the electrode pads are arrayed around a periphery of the main surface of the semiconductor chip.
22. The ultrasonic wire bonding method according to claim 17 , wherein the first electrode pads have a rectangular shape with a long dimension extending along the second direction.
23. The ultrasonic wire bonding method according to claim 17 , wherein the conductive wire has a surface coated with a palladium plating.
Cooperative Patent Classification codes for this invention. Click any code to explore related patents in that topic.
December 22, 2011
October 29, 2013
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